Table 1.

Bacterial strains evaluated and the ΔRQ values generated in PCR with the Pr2a and Pr2c primers and the Yer-prb fluorogenic probe

Bacterium evaluatedΔRQ valueaInterpretationb
Y. enterocolitica (virulent serotypes)
Y. enterocolitica (avirulent serotypes)
Other species of Yersinia
Y. aldovaec2.24Negative
 Y. bercovieric2.05Negative
 Y. frederikseniic2.67Negative
 Y. intermediaic2.71Negative
 Y. kristenseniic1.93Negative
 Y. mollarettic2.29Negative
 Y. pseudotuberculosisf1.85Negative
 Y. ruckeric2.82Negative
Other bacteria
 Citrobacter freudiniif2.24Negative
 E. colig1.26Negative
 E. coliO157:H7g1.49Negative
 Flavobacterium spp.g1.24Negative
 Salmonella enterica serotype chloleraesiusg0.81Negative
 S. enterica serotype Typhimuriumg1.54Negative
  • a Determined with ∼107CFU/ml for each strain.

  • b A positive score is assigned when the ΔRQ is greater than the ΔRQ threshold, based on a fourfold average value of the no-template controls.

  • c From the National Animal Disease Center, United States Department of Agriculture. Ames, Iowa.

  • d From the Centers for Disease Control and Prevention, Atlanta, Ga.

  • e From the Food Microbiology Culture Collection, Kansas State University, Manhattan.

  • f From M. M. Chengappa, Veterinary Diagnostic Laboratory, Kansas State University.

  • g From R. D. Oberst, Food Animal Health and Management Center, Kansas State University.